Nitride semiconductor element and nitride semiconductor package

Abstract

A nitride semiconductor element capable of accommodating GaN electron transfer layers of a wide range of thickness, so as to allow greater freedom of device design, and a nitride semiconductor element package with excellent voltage tolerance performance and reliability are provided. On a substrate (41), a buffer layer (44) including an AlN layer (47), a first AlGaN layer (48) (with an average Al component of 50%) and a second AlGaN layer (49) (with an average Al component of 20%) is formed. On the buffer layer (44), an element action layer including a GaN electron transfer layer (45) and an AlGaN electron supply layer (46) is formed. Thus, an HEMT element (3) is constituted.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a nitride semiconductor element using a group III nitride semiconductor and a semiconductor package of the element.[0003]2. Description of the Related Art[0004]The so-called group III nitride semiconductor refers to a semiconductor formed by using nitrogen as a group V element in a group III-V semiconductor. Representative examples are AlN, GaN, and InN, and generally, may be denoted as AlxInyGai−x−yN (0≦x≦1, 0≦y≦1, 0≦x+y≦1).[0005]This type of group III nitride semiconductor has physical properties suitable for us application in high-temperature, high-power, high-frequency devices. In view of these physical properties, the group III nitride semiconductor is used as a semiconductor in devices such as a High Electron Mobility Transistor (HEMT).[0006]For example, an HEMT having a Si substrate, an AlN layer, an AlGaN layer (with an Al component of greater than 0.3 and below 0.6), a GaN layer...

AI Technical Summary

Benefits of technology

The present invention provides a nitride semiconductor element that can accommodate GaN electron transfer layers of wide range of thickness, allowing greater freedom of device design. The invention also provides a nitride semiconductor element package with excellent voltage withstanding performance and reliability. The invention solves the problem of fine cracks and warping of the Si substrate caused by the difference in lattice constant between the Si substrate and the GaN electron transfer layer. The invention also reduces the difference in lattice constant between the GaN electron transfer layer and the AlGaN layer, which results in complete lattice relaxation and alleviates the problem of alligator cracks and warping of the Si substrate.

Problems solved by technology

Consequently, fine cracks (alligator cracks) are generated on the GaN layer.

This imposes practical limits on GaN layer thickness, thus constraining device design.

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